An Out-of-This-World Diamond

“Twinkle, twinkle little star/ how I wonder what you are/
up above the world so high/ like a diamond in the sky…”

Countless parents have sung that classic song with their
small children without too much thought to the words, but astronomers have
discovered a star is not just like a diamond in the sky. They did more
than wonder what it was, and they have an answer. The star known as BPM 37093
(aka V886 Centauri) is, in fact, an actual diamond the size of a planet. Neither
of its official names are particularly memorable, so scientists have given it a
third name – Lucy, after the Beatles’ song Lucy in the Sky with Diamonds.

What Is the Stars? What Is the Stars?

Joxer in Sean O’Casey’s play Juno and the Paycock wasn’t the
only Irishman to wonder “what is the stars, what is the stars”. Just a few years
after O’Casey penned the play, William Hunter O’Crea completed a PhD at
Cambridge that included calculations demonstrating that the sun was hydrogen
and helium with traces of other elements. McCrea’s work laid the foundation for
how we understand the formation of the solar system and the nature of the sun
itself, which is of course a star.

While the stars we see above us at night are the same ones
that shone above our ancestors throughout the ancient world, these glorious
balls of light do have a life cycle. As the gases of the star burn up, its
light fades, leaving its core, which is comprised mainly of carbon and oxygen.
When a star dies, the remaining core is still hot. Astronomers call this a
white dwarf star, and they theorized that the core of such a star eventually
crystalizes.

Lucy, the Diamond in the Sky

Lucy, a white dwarf star 50 light years away from the Earth in the constellation of Centaurus, captured the attention of astronomers. The star’s temperature had dropped below 12,000 degrees Fahrenheit, and Lucy was pulsating and chiming like an enormous gong.

A team of researchers decided that Lucy was an ideal opportunity to use new technology to confirm the theory that white dwarf stars crystalize, and they discovered that Lucy was 90% crystalized. And crystalized carbon is diamond.

While stars do eventually burn out and die, diamonds are
forever. At 4,000 kilometres across, Lucy tips in at 10 billion trillion
trillion carats. (No, that is not a typo. It’s 10 billion trillion trillion
carats.) This dwarf white star really dwarfs the 546-carat Golden Jubilee
diamond and the famous Hope diamond, which was originally 115 carats. Lucy is
far enough out of our reach to be safe from humans, which means we can all enjoy
looking up at night and wondering if we can spot it. (Tip: It’s best seen from
Florida in the month of May.) Whether we have a collection of diamonds to rival
a royal or one diamond engagement ring, the stars are a treasure for everyone.

All of this begs the question – how many of those twinkling
stars above us really are diamonds?